The way in which data is transmitted from one place to another is called data transmission mode. It is also called the data communication mode. It is indicates the direction of flow of information. Sometimes, data transmission modes are also called directional modes.

Types of Data Transmission Modes
Different types of data transmission modes are as follows:

Simplex mode

Half-duplex mode

Full-duplex mode

1- Simplex Mode
In simplex mode, data can flow in only one direction. In this mode, a sender can only send data and cannot receive it. Similarly, a receiver can only receive data but cannot send it. Data sent from computer to printer is an example of simplex mode.
In simplex mode, it is not possible to confirm successful transmission of data. It is also not possible to request the sender to re-transmit information. This mode is not widely used. However, this mode is used in business field at certain point-of-sale terminals. The other examples of simplex communication modes are Radio and T.V transmissions.

2- Half-Duplex Mode
In half-duplex mode, data can flow in both directions but only in one direction at a time. In this mode, data is sent and received alternatively. It is like a one-lane bridge where two-way traffic must give way in order to cross the other.
The Internet browsing is an example of half duplex mode. The user sends a request to a Web server for a web page. It means that information flows from user's computer to the web server. Web server receives the request and sends data of the requested page. The data flows the Web server to the user's computer. At a time a user can a request or receive the data of web page.

3- Full-Duplex Mode
In full duplex-mode, data can flow in both directions at the same time. It is the fastest directional mode of data communication. The telephone communication system is an example of full-duplex communication mode. Two persons can talk at the same time. Another example of fully-duplex mode in daily life is automobile traffic on a two-lane road. The traffic can move in both directions at the same time.